Albert e



UNITED STATES PATENT OFFICE.

ALBERT E. MILLER, OF PORT ARTHUR, TEXAS, ASSIGNOR TO GULF REFININGCOMPANY, OF PITTSBURGH, PENNSYLVANIA, A CORPORATION OF TEXAS.

PROCESS OF PURIFYING OIL.

No Drawing.

To all whom it may concern:

Be it known that I, ALBERT E. MILLER, a citizen of the United States,residing at Port Arthur, in the county of Jeflerson and State of Texas,have invented certain new and useful Improvements in Processes of Puriing Oil, of which the following is a speci catlon.

This invention relates to processes of puriing oil; and it comprises amethod of furt or treating oils and oily materials which have beensubjected to the action of aluminum chlorid, wherein the oil, after theaction of aluminum chlorid is completed or has been carried as far asmay be desired, is allowed to stand in order to settle out aluminumchlorid mechanically as far as possible and is thereafter treated withlimited amounts of moist air, to fiocculate the suspended or dissolvedaluminum chlorid (or its compounds) so that it may be removed bymechanical means; all as more fully hereinafter set forth and asclaimed.

Anhydrous aluminum chlorid is a readily reactive chemical which hascharacteristic convertin and purifying effects on hydrocarbon oifs. Itmay be used in many ways. In one process of improvin oils, the oiliswarmed with aluminum c lorid, at, say, around 150 F., with agitationfor several hours. When lubricating oil, ior example, is thus treatedvarious changes occur which are here not important to follow, except tostate that the oil is im roved in quality. When the oil is improve tothe extent desired and is allowed to cool to ordinary temperature, mostof the aluminum chlorid compounds settle out as a sludge, while a smallpercentage remains suspended in the oil in colloidal form. Thiscolloidal matter remaining in the oil must be removed and in practiceitis desirable to remove it as soon as the bulk of aluminum chlorid sludhas settled out giving it a deep color an rendering the oil susceptibleto deterioration as long as it is present. In another method of improvinpetroleum oils with aluminum chlorid, crude oil is dried and boiled withaluminum. chlorid for a time. The gasolene and kerosene naturallycontained in the oil, if any, areusually first remo ed by distillation;and this distillation mayeifect the dryin Under the influenceof thealuminum c lorid, more or less of the high boiling oils are convertedinto low bo1l1n oils, such as gasolene, and removed. All t e 011Specification of Letters Patent.

Patented Aug. 5, 1919.

Application filed June 26, 1917. Serial No. 177,051.

may be so converted; but in case it is desired merely to improve thequality of the oil this is not done and the converting action is stoppedwhen the desired amount of oil is converted and the material in thestill cooled down. The greater portion of the alumi- 'num chlorid nowseparates from the residual high boilin oil, but the latter stillcontains a little col oidal aluminum chlorid or its compounds. Aromaticoils, such as coal tar oils are also often treated with aluminumchlorid. In the prior art this suspended colloidal matter in oils sotreated has been removed in a variety of ways. One such way is tosubject the oil to the action of a small amount of sulfuric acid-thesulfuric acid being used solel for the purpose of removing the 'suspened aluminum chlorid or its compounds and not for the usual purpose ofimproving the quality of the oil. It 1s found in practice that agitatingthe oil with a ver small amount of sulfuric acid takes out t e aluminumchlorid or its compounds from the oil, flocculating, coagulatmg andsettling it. In another method the oil is filtered through fullers earthor other gulverulent material with the same result. ften the oil isfirst treated with a little sulfuric acid and then with fullers earth.

I have found that the desired result of fiocculating these colloidalaluminum chlorid compounds and rendering them removable can be achievedin a. simpler and cheaper way, which consists of introducing an extremelsmall amount of moisture into the treate oil in the form of wet air. Thesmall amount of moisture so introduced reacts with the anhydrousaluminum chlorid and converts the colloidal matter intofloccul'entmatter, which, though still remaining sus ended throu houtthe oil, can now be rea i1 re mov by mechanical means, such as tilt tionor agitating with finely divided fullers earth or bauxite. Largeramounts of moisture through decomposin the anhydrous aluminum chloridcause co oring matters to go into solution and do 'not give floccule'ntmatter removable in this way. And excess of moisture is likely to formhydrochloric acid which will go into solution and into the 01 In apractical embodiment of the present invention, after the oil has beentreated with aluminum chlorid for urifying it andwhile it still containsa sma 1 amount of colloidal aluminum chlorid compounds in suspension,

I pass a strong current of moist air or an exceedin ly dilute current ofsteam into the oil. in extremely small quantity of moisture is thusdelivered into the oil which clears it and flocculates the colloids. Themoist air or steam introduction is then discontinued and as much of thefiocculent matter is allowed to settle as possible. I can useatmospheric air in its natural condition or air blown through hot wateror steam delivered through a small orifice. The amount of moisture inatmospheric air is, of course, dependent upon climatic conditions, butordinarily enou h moisture is contained therein to aocom ish m fpurposeby blowing same throng the oii or a period of from two to three hours. Amore ra id method is to blow atmospheric air throug hot water beforeintroducin it into the oil, in which case flocculation is accomplishedin a few minutes. A still quicker method is to use steam with air,introducin it through a small orifice and agitating t e oil with thestream for a few seconds. When the colloidal matter is sufiicientlyflocculated, agitation with wet air or steam is discontinued and the oilcontaining the fiocculent material is treated further according to itscondition. In all cases my object is to use just about enough moistureto produce flocculation but not more. In using moist air the air itselfhas some influence since I ave noted that dried air also producesflocculation, albeit more slowly.

Various other materials capable of acting on anhydrous aluminum chloridmay be used, as for example ammonia. Air containing a little ammonia gasacts quickly and gives a good separation. Solid sodium carbonate orbicarbonate in small quantities may be agitated with the oil. But theuse of moistened air, or of a minute quantity of steam, is the simplestway.

In the case of oils having a viscosity of 100 or below on the Sayboltuniversal .viscosimeter at 100 F., the fiocculent bodies will generallysettle readily to the bottom of thetreatmg vessel. If complete settlingof these bodies does not take place, the small amount remaining insuspension is removed by adding pulverulent inorganic material, such aspowdered bauxite or fir-11ers earth,

to the oil and then agitating the mixture with air for a few minutes. Qndiscontinuing the air agitation, the fullers earth or bauxite settles tothe bottom and carries down with it any small traces of flocculentmatterwhich'may have remained in the oil. The finished oil can then bedecanted from the sediment.

In the case of oils having a viscosity greater-than 100 on the 'Sayb'oltuniversal viscosimeter, after fiocculating the colloids with wet air orsteam, the oils often remain slightly acid, probably with hydrochloricacid. These oils can be made into finished product in several ways, oneof which is to mix pulverulent material, such as powdered bauxite orfullers earth, with the oil and then agitate with air for a few minutes.

After agitation, the mixture is filtered through canvas or coarsefullers earth or bauxite.

A suitable filter for this purpose may be made of heavy canvas or cottoncovered with say, a quarter-inch, of fine freshly burned fullers earth.The object is to use anon h nstead of using the fullers earth or the.

like, the oils after the flocculation in any of the described ways maybe simply washed with a little ium carbonate, and then with water. Aftersettling, the oil may be blown bright with air as before. i

It is often advantageous to add a little powdered calcium carbonate tothe fullers earth in order to neutralize any free acid which may bepresent.

What I claim is 1. In the further treatment of oils which have beensubjected to the action of aluminum chlorid and which still containsuspended or dissolved aluminum chlorid,it he process which comprisesair-blowing'snch an oil until the aluminum chlorid is converted into aform readily settling out.

2. In the further treatment of oils which have been subjected to theaction of aluminum chlorid and which still contain suspended ordissolved aluminum chlorid, the process which comprises air-blowing suchan oil with moist air until the chlorid is converted into a form readilysettling out.

3. In the further treatment of oils which have been subjected to theaction of aluminum chlorid and which still contain suspended ordissolved aluminum chlorid, the pron ess which comprises blowing airthrough water and then through the oil to be treated.

4. In the further treatment of oils which have been subjected to theaction of aluminum chlorid and which still contain suspended ordissolved aluminum chlorid, the proc- LED ess which comprises reactingupon the oil with a reagent adapted to convert anhydrous aluminumchlorid into a flocculated form and. treating the oil with fullers earthcontaming a little calcium carbonate.

5. In the further treatment of oils which num ehlorid and which'stillcontain suspendhave been subjected to the action of alumied or dissolvedaluminum ehlorid, the proc num chlorid and which still containsuspendess which comprises hgdrat'mg the anhyed or dissolved aluminumchlorid, the procdrous aluminum chlori to produce a floc- 5 ese whichcomprises hydratig dg the anhyculent readily settling suspension andthere- 15 drous aluminum chlorid to pr uce a fioccuafter treating theoil with an alkaline agent lent readily settling suspension and thereandfuilers earth. after treating the oil with an alkaline aggant. Intestimony whereof, I afiix my signature 6. In the further treatment ofoils w ich hereto.

10 have been subjected to the action of alumi- ALBERT E. MILLER.

